1. Field of the Invention
The present invention relates to data reception systems for storing and reproducing received data and, more specifically, to a data reception system which is capable of replacing a faulty recording medium having data recorded thereon for data recovery.
2. Description of the Background Art
Computers use a recording medium, such as a hard disk, to store a large amount data. Such a recording medium may, however, fail often. When the hard disk fails, the hard-disk manufacturing and sales company generally guarantees to provide an alternative hard disk, but does not guarantee to recover lost data. For example, hard disks manufactured by Seagate Technology Inc. (marketed by Kabushiki Kaisha Synnex in Japan) bear warranty guaranteeing to replace for free the hard disk that fails during a two-year warranty period, but not guaranteeing to recover the data that is recorded on the faulty hard disk.
Meanwhile, with an increase in the capacity of hard disks, storage-type video distribution services using such hard disks have been suggested, and a specific example thereof is disclosed in Japanese Patent Laid-Open Publication No. 2000-278618. In this service, video data with a certain limitation is distributed from a server to a receiver. The distributed video data is recorded on a hard disk which is incorporated in the receiver. A viewer views video within that limitation. Some video data can be possessed for an indefinite period of time, such as data that is recorded on a video tape or a DVD (Digital Versatile Disk). Some video data has a limitation on the number of it can be viewed times or the viewable period. In a storage-type video distribution service, the more the hard disk has video data recorded thereon, the more valuable the hard disk becomes.
As stated above, however, hard disks fail due to various reasons. If a hard disk with a large amount of video data recorded thereon fails, what matters is the recorded data, rather than the hard disk itself. Therefore, in this case, data recovery is more desired than hard disk replacement.
Also, hard disks have increased in capacity so rapidly that hard disks having a capacity of over several Tbytes (terabytes) are expected to come along in several years. Such hard disk can have video data of several hundred hours recorded thereon. Therefore, to viewers who enjoy the storage-type video distribution service, managing and backing-up such a large amount of data on their own will be quite burdensome to the viewers. If the large-capacity hard disk having a large amount of data recorded thereon fails once, financial damage caused thereby will be enormous.
The above-described problems will occur not only when the hard disk fails but also when it is replaced with another hard disk. For example, consider a case where a viewer desires to buy a new receiver to replace the existing one. In this case, if video data that is stored in the hard disk of the existing receiver cannot be moved into the new one, the viewer is deemed to abandon the right of viewing the video data that is recorded on the original hard disk. Also, the increase in the hard disk capacity is so rapid that hard disks become obsolete earlier than ever before. Therefore, the hard disk may become obsolete earlier than the receiver that incorporates it. In this case, some viewers may replace the hard disk with a new one but still use the receiver. Replacing the hard disk is not a difficult task for viewers. Transferring data from an old hard disk to a new one is, however, not an easy task for every viewer because it requires some special apparatus and expert knowledge. Furthermore, removal of the hard disk from the receiver is sometimes restricted in view of ensuring the capability of the receiver.
One way to solve the above-described problems is copying the video data to various media such as video tapes. In practice, however, it is quite difficult to copy the entire data that is recorded on the hard disk having a large capacity such as several Tbytes. If copying is made, the viewer has to manage a large number of media with the copied data, which is quite burdensome.